3D TV a Different Way

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3D TV a Different Way

Postby Lawnboy » Sun Dec 28, 2014 11:59 am

Recently I was inspecting some Christmas decorations that used lenticular lenses to give a 3D effect, and started thinking if something similar could be done with NBTV. Here's what I came up with so far. If a vertically oriented mirror drum were used, a pair of modulated lasers should be able to draw a pair of lines right next to each other on a translucent screen, each laser drawing the same line from its associated stereo image. If a suitable lens were placed directly over this screen, then the lens should distribute the images toward the appropriate eye. Any thoughts?
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Re: 3D TV a Different Way

Postby Panrock » Thu Jan 01, 2015 6:26 am

Hi Lawnboy.

I don't claim to understand in depth how lenticular lenses 'work' to create 3D but I can't see any obvious objection to your proposal. Equally though, you could have just a vertical grille arranged so its lines could cut off one or other of the rasters to each eye. You'd need to view at the correct distance though. I think Baird used this arrangement at one point.

I have attempted 3D NBTV in the past. The rig shown here switched between left and right frames alternately. There was of course massive 6¼Hz flicker but I did find the brain's two hemispheres would integrate the left-right flicker, making it look like 12½ Hz again!

I also have used lenticular lenses before, but only in an invention called the 'Copycoder'. Here, the lenses are stacked side-by-side and (simplifying slightly) they are twice as thick as their focal lengths - so a mirror image of each lenticular section is created at a magnification of x1. Twist the array by 40 degrees and - bingo! :)

Steve O
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Re: 3D TV a Different Way

Postby DrZarkov » Thu Jan 01, 2015 6:56 pm

How about Karen Orton's mirror-disc with the hat-needles? It is a kind of "flat mirrorscrew", with the advantage of linticular mirrors (hat-needles). When Karen presented this disc at the convention, she mentioned the disadvantage of the parallax, that you see different pictures with your two eyes. It should work to use this disadvantage as an advantage, if you use two light sources for two different pictures. This would of course only work with one spectator, looking from the right angle to the disc.

PS: happy new year everyone. :D
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